AIDS-related morbidity and mortality has decreased greatly with the advent and use of highly active antiretroviral therapy (HAART). The incidence of some AIDS-defining cancers (Kaposi's sarcoma and non-Hodgkin's lymphoma) has declined significantly with the widespread use of HAART, while incidence rates of other cancers that are considered to be increased in HIV-infected people (including Hodgkin's disease, cervical cancer and anal cancer) have shown no change in the post-HAART era. To further explore the effect of HAART on cancer incidence at the population level, we propose to match San Francisco AIDS cases diagnosed for the years 1990 through 2000 with California cancer cases diagnosed for the years 1988 through 2000. This match will allow us to examine the effect of HAART on temporal trends in both AIDS-defining cancers and non-AIDS-defining cancer incidence among AIDS patients in San Francisco. We will compare the time before HAART was introduced (1988-Nov 1995) to the years when HAART was widely available (Nov 1995- 2000). In addition, we will assess cancer survival time with immunologic status and clinical presentation of both AIDS-defining and non-AIDS-defining cancers among AIDS patients who use HAART and those who do not. Changes in morbidity and mortality among persons with AIDS are readily apparent in San Francisco, a national metropolitan area with the third most cumulative AIDS cases and a city in which over three-fourths of persons with AIDS have received HAART. The completeness of AIDS case reporting in San Francisco is 97% and follow-up chart review of AIDS cases is completed every 18 months providing up-to-date information regarding treatment use and diagnoses with subsequent AIDS diagnoses. The California Cancer Registry is one of the largest cancer registries in the world with approximately 120,000 new cases reported each year and is internationally recognized for its high quality cancer data. The San Francisco Department of Public Health AIDS registry provides a complete population-based dataset of AIDS cases in San Francisco allowing us to evaluate the impact that HAART use and improved survival with AIDS has on subsequent development of cancers. Given the respective strengths of the AIDS and cancer registries, we are uniquely situated to perform these investigations.